Fix LMS return statements having incorrect style

Signed-off-by: Raef Coles <raef.coles@arm.com>
diff --git a/library/lmots.c b/library/lmots.c
index 1639587..1e27024 100644
--- a/library/lmots.c
+++ b/library/lmots.c
@@ -92,7 +92,7 @@
         val |= ( ( unsigned int )bytes[idx] ) << (8 * ( len - 1 - idx ) );
     }
 
-    return val;
+    return ( val );
 }
 
 /* Calculate the checksum digits that are appended to the end of the LMOTS digit
@@ -117,7 +117,7 @@
         sum += DIGIT_MAX_VALUE - digest[idx];
     }
 
-    return sum;
+    return ( sum );
 }
 
 /* Create the string of digest digits (in the base determined by the Winternitz
diff --git a/library/lms.c b/library/lms.c
index 321e51a..b460353 100644
--- a/library/lms.c
+++ b/library/lms.c
@@ -736,7 +736,7 @@
     if ( MBEDTLS_LMS_SIG_LEN(ctx->params.type, ctx->params.otstype)
          < SIG_OTS_SIG_OFFSET )
     {
-        return MBEDTLS_ERR_LMS_BAD_INPUT_DATA;
+        return ( MBEDTLS_ERR_LMS_BAD_INPUT_DATA );
     }
 
     ret = mbedtls_lmots_sign( &ctx->ots_private_keys[q_leaf_identifier],